Commercial scale floating cage systems for the culturing of fish and other aquatic animals are known although the industry is relatively underdeveloped in terms of practical design and operational experience. Accordingly, numerous cage designs have been proposed, none of which has proven completely successful in terms of cost, durability, biological compatibility and economic viability. Most designs, including the present one, share a number of features in common, including a buoyant framework defining the cage, a net or perforated panels supported on the inside or outside of the frame to define an enclosure, means to support the cage for rotation about a central axis so that individual surfaces or portions of the net can be periodically exposed to ambient air for cleaning, repair or replacement and a mechanism for submerging the cages in the event of violent weather, ice, lethally cold water, toxic bloom and other surface hazards.